A hospital death rate is often referred to as the mortality rate. The hospital mortality rate tracks the number of deaths that occur in a hospital during inpatient admissions. This includes any death that occurred for a particular set of primary diagnoses. A primary diagnosis is the main reason someone was admitted to the hospital. The death must have occurred while the patient was admitted to the hospital. The mortality rate is tracked over a 30 day period. This information is tracked by the Centers for Medicare and Medicaid Services (CMS). The information is reported to hospital administration and is often used for quality purposes.